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arXiv · 2107.05919

Periodic cavity state revivals from atomic frequency combs

Matthias Zens·Dmitry O. Krimer·Himadri S. Dhar·Stefan Rotter
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Abstract

Spin ensembles with a comb-shaped spectrum have shown exciting properties as efficient quantum memories. Here, we present a rigorous theoretical study of such atomic frequency combs in the strong coupling limit of cavity QED, based on a full quantum treatment using tensor-network methods. Our results demonstrate that arbitrary multi-photon states in the cavity are almost perfectly absorbed by the spin ensemble and re-emitted as parity-flipped states at periodic time intervals. Fidelity values near unity are achieved in these revived states by compensating for energy shifts induced by the strong spin-cavity coupling through adjustments of individual coupling values of the teeth in the atomic frequency comb.

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Matthias Zens, Dmitry O. Krimer, Himadri S. Dhar, Stefan Rotter. 2021-07-13. Periodic cavity state revivals from atomic frequency combs. https://doi.org/10.1103/physrevlett.127.180402

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